TRIM No: D2016/83578 Market Operator National Meter Identifier Allocation Procedure Content 1. Purpose ...................................................................................................................................1 2. Scope ......................................................................................................................................1 3. Roles and Responsibilities .........................................................................................................2 4. Definitions ...............................................................................................................................2 5. Principles .................................................................................................................................3 6. References...............................................................................................................................6 7. Appendices ..............................................................................................................................6 8. Records ...................................................................................................................................6 9. Review ....................................................................................................................................6 10. Document History.....................................................................................................................6 Appendix A: NMI Source ...................................................................................................................7 Appendix B: NMI Structure ...............................................................................................................8 Appendix C: NMI checksum ..............................................................................................................9 Appendix D: NMI data stream suffix ................................................................................................ 14 Appendix E: NMI allocation to metering installation types .................................................................. 17 Appendix F: Examples for the allocation of NMIs............................................................................... 18 1. Purpose The purpose of this procedure is to specify the key principles to be adopted by the Network Operator for allocation of NMIs to metering installations in the NT electricity supply industry and the key principles to be adopted by the Market Operator for the registration of those NMIs. 2. Scope This document applies to: • The allocation of NMIs to metering installations in all electricity supply regions, as well as major and minor centres in the NT. The NMI is to uniquely identify: o a metering installation in the network where a meter is used to measure the flow of electricity (either into, across or out of the network); o an agreed metering installation for non-metered loads that are billed by a retailer to a customer • The I-NTEM and the NTEM (as it is currently understood) • The initial purpose built settlements system for the I-NTEM for its life span • The AEMO Market Settlements and Transfer Solutions (‘MSATS’) at the time it is introduced into the I-NTEM or the NTEM. For the removal of doubt: • The UMI will be superseded by the NMI at all customer locations in the NT. • The NMI does not uniquely define a connection point, even though there are a number of connection points with only one metering installation and hence one NMI. • There may be more than one metering installation at connection point and this principle should be preserved when defining the NMI relationship. That is, NMIs are not to be allocated solely for the purpose of uniquely identifying network connection points.
Transcript
TRIM No: D2016/83578
Market Operator National Meter Identifier Allocation Procedure
1. Purpose The purpose of this procedure is to specify the key principles to be adopted by the Network Operator for allocation of NMIs to metering installations in the NT electricity supply industry and the key principles to be adopted by the Market Operator for the registration of those NMIs.
2. Scope This document applies to:
• The allocation of NMIs to metering installations in all electricity supply regions, as well as major and minor centres in the NT. The NMI is to uniquely identify: o a metering installation in the network where a meter is used to measure the flow of
electricity (either into, across or out of the network); o an agreed metering installation for non-metered loads that are billed by a retailer to a
customer • The I-NTEM and the NTEM (as it is currently understood) • The initial purpose built settlements system for the I-NTEM for its life span • The AEMO Market Settlements and Transfer Solutions (‘MSATS’) at the time it is introduced into
the I-NTEM or the NTEM.
For the removal of doubt:
• The UMI will be superseded by the NMI at all customer locations in the NT. • The NMI does not uniquely define a connection point, even though there are a number of
connection points with only one metering installation and hence one NMI. • There may be more than one metering installation at connection point and this principle should be
preserved when defining the NMI relationship. That is, NMIs are not to be allocated solely for the purpose of uniquely identifying network connection points.
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• If the principle of embedded networks is adopted in the NT, the allocation NMIs to metering installations in that network will follow the principles in this procedure. That is, there will be no unique identifier for the embedded network.
3. Roles and Responsibilities Role / Title Responsibility
Senior Executive Manager Commercial and Legal
• Approve this procedure.
• Ensure that this procedure is complied with during its application.
• Consult on the procedure when it is prepared and at any time it is substantially changed so that the NMI allocation process represents an arrangement agreed by I-NTEM Market Participants and other regional participants.
• Implement the procedure in regard to the registration of NMIs against settlement points.
• Implement the procedure to ensure that all metering installations have a NMI, subject to a reasonable plan to transition from the UMI to the NMI.
Stakeholders • Adopt the NMI as the unique reference to a metering installation for the purpose of customer transfers.
4. Definitions The definitions of words recorded in the Glossary of the System Control Technical Code apply to this document, in addition to the words recorded in the table below, as shown in italics throughout the document.
Word Definition AEMO Australian Energy Market Operator Connection point The point at which electricity is transferred to or from an
electricity network. A connection point can be an entry point to or an exit point from a network, as defined in the Electricity Networks (Third Party Access) Code.
I-NTEM Interim Northern Territory Electricity Market. The Electricity Market in the Darwin – Katherine power system that commenced in May 2015.
Market Operator
The NT entity that manages the wholesale exchange of electricity based on the System Control Technical Code. Power and Water is the Market Operator in the I-NTEM.
Metering installation The assembly of components including the instrument transformer, if any, measurement element(s) and processes, if any, recording and display equipment, communications interface, if any, that are controlled for the purpose of metrology and which lie between the metering point(s) and the point at or near the metering point(s) where the energy data is made available for
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Word Definition collection. Notes:
(1) The assembly of components may include the combination of several metering points to derive the metering data for a [settlement point at any] connection point.
(2) The metering installation must be classified as being for revenue purposes and/or as a check metering installation.
(3) An unmetered connection point in accordance with schedule 7.2 does not require a meter; it is nevertheless considered as having a metering installation.
Metering point The point of physical connection of the device measuring the flow of electricity in the power conductor.
NEM National Electricity Market Network Operator The Power Networks business unit within the Power and Water
Corporation for the NT. NMI A National Meter Identifier as described in clause 7.3.1(d) of the
National Electricity Rules. NT Northern Territory NTEM Northern Territory Electricity Market – a future upgrade of the
I-NTEM market design Power and Water The Power and Water Corporation Service point The physical point of service of a network; a term used
interchangeably with the term connection point within the Power and Water enterprise systems.
Stakeholders Market Participants and System Participants UMI The unique identifier assigned to an exit point by a network
provider, as stated in the Retail Supply Code. Commonly referred to as the ‘Unique Meter Identifier’.
5. Principles The following principles are to be used to guide the allocation of the NMI in the NT: 5.1. Source of NMIs:
5.1.1. NMIs are available as a block from AEMO for use in the NT (refer to Appendix A ‘NMI source’ for details).
5.1.2. The block of numbers is to be assigned by the Market Operator to each of the NT electricity supply power systems in accordance with the list provided in Appendix A.
5.2. The Network Operator must issue for each metering installation a unique NMI. For the removal of doubt:
5.2.1. There may be more than one metering installation at any one connection point. Consequently, there may be more than one NMI at any one connection point.
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5.2.2. There will only be one metering installation at any one settlement point1. Consequently, there will be a one-to-one relationship between a settlement point and a NMI.
5.2.3. Any one metering installation may be formed from an assembly of the components from two or more standalone metering installations.
5.3. The NMI is to be allocated to the following metering installations:
5.3.1. Metering installations that contain interval meters
5.3.2. Metering installations that contain accumulation meters
5.3.3. Metering installations that do not contain a meter but are to be used in the wholesale settlements process (for example, street lights)
5.3.4. Metering installations at wholesale market boundary points
5.3.5. Metering installations at customer settlement points
5.3.6. Metering installations in embedded networks.
5.4. The Network Operator must register each metering installation (and its NMI) that has been allocated to a generator, a retailer or a customer with the Market Operator.
5.4.1. The following information must be provided to the Market Operator:
(a) NMI
(b) Address, including street identifiers and postcode
(c) The identity, characteristics and serial numbers of the metering installation components2 (such as meter, instrument transformers, modem)
(d) Loss Factor Code
(e) Embedded network parent and child names (if any)
(f) Network node identifier (being: generator, bulk settlement point or customer, as the case may be).
5.4.2. For the removal of doubt, Power Networks within Power and Water will perform the following roles in the NT. This information is not required to be recorded against the metering installation at the time of registration:
(a) Metering Coordinator
(b) Metering Provider
(c) Metering Data Provider.
5.5. NMI structure. The NMI is a basic ten numeric digit number. The NMI may be used in conjunction with other identifiers or suffixes, which are explained in Appendix B ‘NMI Structure’.
5.6. NMI checksum. A one digit checksum feature must be used to reduce the occurrence of incorrect transfers attributable to manual data entry errors. This feature is explained in Appendix C ‘NMI checksum’.
5.7. NMI data stream suffix. From any one metering installation there could be multiple data streams3. The number of data streams at a connection point increases when multiple metering installations are registered at that location. The accurate identification of data streams is explained in Appendix D ‘NMI data stream suffix’.
1 A ‘settlement point’ in this paper means the agreed point of supply where electricity is financially transacted between a retailer and a customer. There may be one or more settlement points assigned to a connection point. It is used in this paper to emphasise the difference between the purpose of a metering installation and the purpose of a connection point. 2 As determined by the Market Operator from time to time. 3 For example, import and export data streams for both kWh and KVArh.
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5.7.1. For the purpose of assigning the correct characters for import and export to an NMI suffix, the energy flow directions are to be followed4:
(a) Import is where electricity enters a network, either from a source of generation or from another network – it is assigned the first suffix character B.
(b) Export is where electricity exits a network, either to a load or to another network – it is assigned the first suffix character E.
5.8. NMI allocation at the wholesale market boundary5. At the boundary between the wholesale market network and a distribution network, there are two different types of settlement points. One is a physical point and the other is a virtual point6.
5.8.1. The physical settlement point must have a physical metering installation and hence an NMI.
5.8.2. The virtual settlement point will be established by the Market Operator to allow a customer’s metering installation to be referred to that point (under certain circumstances7) for the purpose of settlements. A virtual settlement point will also be assigned an NMI, which is different to that assigned to the physical metering installation.
5.8.3. The Market Operator will request the Network Operator to allocate an NMI to the metering installation that will be assigned to the virtual settlements point.
5.9. NMI allocation to metering installation types. NMIs are to be allocated differently in accordance with the requirement to use check metering installations in certain situations. The treatment of NMIs when both master and check metering installations are deployed are explained in Appendix E ‘NMI allocation to metering installation types’.
5.10. NMI rules. The following rules are to apply to the use of an NMI:
5.10.1. The Network Operator must register the basic ten digit NMI with the Market Operator.
5.10.2. The Metering Data Provider must add appropriate identifiers to the end of the NMI (suffix) to enable the Market Operator to identify the characteristics of the data stream collected from any one meter. These identifiers are explained in Appendix D ‘NMI data stream suffix’.
5.10.3. Whilst a customer may elect to change its retailer, the NMI at the settlements point remains assigned to the metering installation.
5.10.4. Whilst a customer may move in and out of a premise that contains an NMI, there will be no change to that NMI at that premise.
5.10.5. An NMI cannot be assigned to another settlement point, other than for the following conditions:
(a) When an NMI is assigned to a builder’s temporary supply, the NMI may be re-used on the permanent supply once the building work has been completed.
(b) If there is a consolidation of metering (eg. change from 3 meters to 2 meters) or a relocation of the meter box without changes to the location of the measurement transformers the NMI will remain unchanged.
4 A diagrammatic representation of this principle can be found in Section 15 of the AEMO NMI Procedure. 5 The wholesale market boundary is the set of agreed points of supply that distinguish the interface
between the wholesale market and the rest of the market, being the points of supply that are utilised by the Market Operator for settlements of the I-NTEM and the NTEM in accordance with the System Control Technical Code.
6 Also known as ‘logical’ in the NEM. 7 This will be activated if the I-NTEM (or subsequent design changes) adopts the settlements by differences
technique used by the NEM for transacting metering data in the market.
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(c) A reconstruction of the customer service connection (eg. overhead changed to underground) in which the two services are not concurrently operational and, without a change of the connection point to the network, does not require a change of NMI.
5.10.6. All communications to and from Market Participants and the Metering Coordinator must include the NMI.
5.10.7. Transfer of all meter data to the Market Operator must be in an agreed format that includes NMI identification.
5.11. Examples for the allocation of NMIs are explained in Appendix F ‘Examples for the allocation of NMIs to interval meters’.
6. References # Document Date Location 1 Systems Control Technical Code v5 (2015) 23/05/2016 D2015/414673 2 NMI Procedure (NEM) August 2009 AEMO website 3 NMI Allocation List, v8 (NEM) December 2014 AEMO website 4 Retail Supply Code 1 June 2013 UC Website 5 Electricity Networks (Third Party Access) Act 1 July 2015 UC Website
7. Appendices 7.1. Appendix A: NMI source
7.2. Appendix B: NMI structure
7.3. Appendix C: NMI checksum
7.4. Appendix D: NMI data stream suffix
7.5. Appendix E: NMI allocation to metering installation types
7.6. Appendix F: Example for the allocation of NMIs.
8. Records This procedure is to be stored in Power and Water’s Records Management System (TRIM) in accordance with the Document and Record Control Procedure.
9. Review This document is to be reviewed no later than three years, or more frequently as required by the Market Operator.
10. Document History Date of Issue Version Prepared By Description of Changes 07/03/2016 V01 Phacelift Initial version
For clarification on the use of this document, please contact: Jodi Triggs Power and Water Corporation in the role of Market Operator Phone: 08 8985 8456 Email: [email protected] NOTE: This document is under consultation, stakeholders please send your submissions to [email protected]. Consultation closes 2pm Monday 11 April 2016.
Power & Water acting as the Market Operator ABN: 15 947 352 360
For enquiries, please call: 08 8985 8459
Appendix A: NMI Source An NMI is a basic ten digit number that can be expanded by adding designated suffixes to identify specified characteristics of the data streams within the metering installation.
AEMO has assigned the following series of numbers (‘block’) to the NT for use as NMIs8:
First NMI in the block: 2500000000
Last NMI in the block: 2509999999
The Market Operator is the custodian of this block of numbers.
The Market Operator has determined to assign the NMI block across the NT in the following way:
Darwin – Katherine power system: 2500000000 to 2500999999
Alice Springs power system: 2501000000 to 2501999999
Tennant Creek power System: 2502000000 to 2502999999
Yulara power system: 2503000000 to 2503999999
Kings Canyon: 2504000000 to 2504999999
Timber Creek: 2505000000 to 2505099999
Elliott: 2505100000 to 2505199999
Borroloola: 2505200000 to 2505299999
Daly Waters: 2505300000 to 2505399999
Ti Tree: 2505400000 to 2505499999
Nhulunbuy: 2506000000 to 2506099999
Alyangula: 2506100000 to 2506199999
Jabiru: 2506200000 to 2506299999
Indigenous Essential Services (IES) non-grid connected: 2507000000 to 2507999999
Other: 2508000000 to 2509999999
Note: in each of the above series of numbers, the following protocol is to be adopted in allocating NMIs to the wholesale market boundary and street lights.
(a) Wholesale market boundary: The first 1,000 numbers in the series is to be allocated to the wholesale market boundary metering installations. For example, in the Darwin – Katherine power system the group of numbers 2500000000 to 2500001000.
(b) Street lighting: The last 10,000 numbers in the series is to be allocated to street lighting metering installations. For example, in the Darwin – Katherine power system the group of numbers 2500999000 to 2500999999.
8 See ‘NMI Allocation List, v8’ on the AEMO website.
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Appendix B: NMI Structure The base NMI is ten characters. In some circumstances the NMI checksum is appended to the NMI to form an eleven-character NMI, or the two character NMI data stream suffix may be appended to form a twelve-character NMI.
The NMI checksum is not used with the data stream suffix because the data stream suffix is intended for use only with electronic data transfer, whereas the NMI checksum is intended for use during manual entry of data.
The key attributes of the NMI are:
• The NMI must embody only numeric characters, except as explicitly provided within this document, and must not contain spaces.
• Character letters ‘O’ and ‘I’ are not permitted in order to avoid confusion with numbers 0 and 1.
• Embedded characters or meanings should not be used in allocating NMIs.
• The Network Operator must:
o only use the NMIs obtained from the Market Operator
o allocate a unique NMI to each metering installation in the NT for which it is responsible
o not re-use an NMI that has been allocated to a metering installation when that installation is no longer active (or ‘on-market’)
o maintain a register of all NMIs allocated to metering installations.
• The Market Operator must maintain a register of all ‘on-market’ NMIs within its market systems.
The relationship between the defined points at the boundary of a network is shown in diagram B1:
Diagram B1 – relationship between defined points at a network boundary
In the diagram the customer is responsible for the electricity used beyond the connection point. Consequently, the settlement point should be shown co-incident with the connection point. However, for visualisation purpose, the settlement point is shown below the connection point and is used as a means of conceptualising the difference between the connection point and the impact of the metering installation. The metering installation includes the metering point and the losses between the metering point and the connection point, as shown by the dashed box.
network
connection point
settlement point
metering point
Defined point for connection of the network to customer assets
Conceptual point for purchase of electricity
Defined point for the location of the meter
metering installation
One per customer
One or more per customer
One per metering installation (settlement point)
customer
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Appendix C: NMI checksum To reduce the occurrence of incorrect transfers attributable to NMI data entry errors, a one digit checksum has been implemented. The NMI checksum is a single numeral used to assist with data validation when the NMI is manually entered into a computer system. The NMI checksum is not used in conjunction with the NMI data stream suffix. However, when publishing an NMI for end-use customers the NMI will appear in its 11-character format and the checksum will be the final character of the NMI.
The NMI checksum is a mandatory field whenever an NMI is manually entered into the Market Operator’s relevant market system.
Sample java code for an implementation of the checksum is provided in C1 below.
A general form of the algorithm used to create the NMI checksum is:
1. Double the ASCII value of alternate digits within the NMI beginning with the right-most digit.
2. Add the individual digits comprising the products obtained in step 1 to each of the unaffected ASCII value digits in the original number.
3. Find the next highest multiple of 10.
4. The check digit is the value obtained in step 2 subtracted from the value obtained in step 3.
5. If the result of this subtraction is 10 then the check digit is 0.
A worked example of the algorithm is provided in C2 below.
The NMI checksum is always a numeric character.
The NMI checksum is not mandatory when transferring NMI identified data electronically between Participants and service providers. The checksum is focused on applications where data entry occurs and there is a risk of character transposition, for example from paper to electronic systems or through an interactive telephone service.
C1: Sample java code for the NMI checksum:
/** * Calculates a LUHN-10. * <PRE> * 1. Double the value of alternate digits beginning with the rightmost digit * 2. Add the individual digits comprising the products obtained in step 1 to * each of the unaffected digits in the original number. * 3. Find the next highest multiple of 10 * 4. The check digit is the value obtained in step 2 subtracted from the value * obtained in step 3. * 5. END * </PRE> */ public class LUHN10 { /** * Value to indicate we have not calculated the luhn yet. */ private static final int NULL_VALUE = -1; /** * Buffer holding the sequence of digits to use in the calculation. */ private StringBuffer _buffer;
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/** * The cached value for the luhn. */ private int _luhn; /** * Constructor. */ public LUHN10() { reset(); } /** * Resets the calculator to its initial values. */ public void reset() { _buffer = new StringBuffer(); _luhn = NULL_VALUE; }
This following worked example demonstrates the NMI checksum calculation. The logic of the algorithm can be summarised as:
• Process each character in the NMI individually, starting with the right most. • For each character:
o Convert the character to its ASCII value o For the right most character and each alternate character reading left, double the ASCII
value obtained in Step 3 above.
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o Add the individual digits of the ASCII value to a register holding the total added value for the Checksum.
• Subtract the total added value register from the next highest multiple of 10. • If the result is 10, the checksum is 0, otherwise the result is the checksum.
The NMI for the following worked example is 1234567890
Step 1. Initialise variables used by the process.
Double_This_Char is a Boolean that indicates whether the character currently being processed should be doubled.
Char is the character currently being processed, as it appears in the NMI.
ASCII_Char is the ASCII value of Char
Total is the running sum of the digits generated by the algorithm.
Checksum is the final result.
At the start of the process: Double_This_Char = True because the right most character, and then every alternate character, is doubled by the algorithm. Total = 0 Checksum = NULL
Step 2. Read the NMI character by character, starting with the right most character.
Char = 0 [TotalBefore]
Step 3. Convert the character to its ASCII value.
ASCII_Char = 48
Step 4. Double the ASCII value if the character is the right most of the NMI or an alternate.
ASCII_Char = 96
Double_This_Char = Not Double_This_Char
Step 5. Add the individual digits of the ASCII value to the Total.
Total = TotalBefore + 9 + 6 (i.e. Total = 15)
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Performing steps 2 through 5 for each character in our example NMI gives the following results:
Character Total Before ascii value Double? Doubled Value Total After
0 0 48 Y 96 15 (0+9+6)
9 15 57 N 57 27 (15+5+7)
8 27 56 Y 112 31 (27+1+1+2)
7 31 55 N 55 41 (31+5+5)
6 41 54 Y 108 50 (41+1+0+8)
5 50 53 N 53 58 (50+5+3)
4 58 52 Y 104 63 (58+1+0+4)
3 63 51 N 51 69 (63+5+1)
2 69 50 Y 100 70 (69+1+0+0)
1 70 49 N 49 83 (70+4+9)
Table C1: Example for NMI 1234567890
The value of Total after processing the entire NMI is 83.
The next highest multiple of 10 is 90.
Checksum = 90 – 83 = 7.
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Appendix D: NMI data stream suffix Settlement of the I-NTEM and other regions is reliant on the collection and delivery of metering data from initially ~3,000 metering installations, with the total rapidly growing up to ~100,000 metering installations as accumulation meters are converted to interval meters.
For any particular metering installation (and hence a given settlement point and connection point) there may be multiple energy measurement elements and data recorders with multiple channels. Accurate identification of data streams is essential. The data stream suffix provides identification at the measurement element level for all data streams comprising the metering installation identified by the NMI.
The data stream suffix is a two character identifier used in conjunction with a ten digit NMI to identify a particular data stream associated with that NMI (making 12 characters in total). The data stream suffix allows differentiation of measurement quantities at a metering point and differentiation of quantities between different measurement elements or registers for a metering installation at its settlement point and connection point.
A twelve character NMI string identifies the metering installation (first ten characters) and associated data stream (data stream suffix as the last two characters).
The data stream suffix has retained alpha numeric characters because an all numeric structure could not accommodate the variety of data types or number of meters which may be required for the metering installation.
The data stream suffix is used when transmitting data between the Market Operator, Market Participants and the Metering Data Provider within the NT – it is not used in conjunction with the NMI checksum. The data stream suffix allows the parties to identify data at a sub-connection point level and to identify the individual sources of meter data to maintain necessary data audit trails.
The following two sections and tables detail the usage of the characters comprising the data stream suffix.
Interval metering data
Interval metering data is metering data in trading intervals or sub-intervals of trading intervals. It may be sourced from metering installations type 1 to 5 or 7. Metering data from a type 6 metering installation which has been transformed through a profiling algorithm into trading intervals is also identified as interval metering data (such as is performed for the IES Communities where there is no statistical bulk meter at the entrance of the community).
Interval metering data is identified in the data stream suffix by a suffix first character that is alpha [A to H, J to N, P to Z].
Identifiers in the MASTER column are those used within the NEM – they will be utilised for the I-NTEM. Where check metering is required (type 1 & 2 metering installations), identifiers from the CHECK column are used for the check installation.
Where the data from the MASTER and CHECK installations has been averaged (due to the metering installations being identical) the AVE column identifiers are used. Where only the difference between import and export is required, the NET column identifiers are used.
NET data is not to be used in the I-NTEM, as the contributions from both import and export to the market are required for policy analysis.
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Data stream First Character Second character
AVE MASTER CHECK NET
Import kWh A B C
N
Meter numbers or measuring elements are
to be 1–9 then A–H, J-N, P-Z
Export kWh D E F
Import kAVrh J K L
X Export kVArh P Q R
KVAh S T U
Power Factor Pf G
Q metering Qh H Y
Par metering path M W
Volts (or V2h) or Amps (A2h)
V Z
Table D1: data stream suffices for interval metered data
Where a meter has multiple measurement elements, the convention for the population of the second character of the data stream suffix is:
• Increment the second character by one if the first character is the same. For example, use E1 and E2 if both elements are export kWh and B1 and B2 if they are both import kWh. Use the same second character if the first character is different. For example, use E1 and B1 if they are export kWh and import kWh respectively.
• Example: 2500010101 E2 relates to Export kWh data from either meter no.2 (single element) or element 2 of meter no.1 (twin element) pertaining to the connection point having the assigned NMI of 2500010101. Refer to Appendix F1.4 & 1.5 for diagrammatic examples.
Accumulation energy data
Refer to the table below:
If the first character of the data stream suffix is numeric (1 to 9) the attached data is accumulation energy data from a type 6 metering installation.
The data streams identified by characters 1 to 6 are active energy (kWh). Data streams identified with 7, 8 or 9 are as defined by the Network Operator.
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Suffix Register Description Meter number
1 First register
Meter numbers are to be 1–2 then A–H, J–N, P–Z.
2 Second register
3 Third register
4 First control load register
5 Second control load register
6 Third control load register
7 First Network Operator defined register
8 Second Network Operator defined register
9 Third Network Operator defined register
Table D2: Data Stream suffixes for consumption energy data
Examples:
• 2500012345 1A relates to accumulation energy data from meter A (the 10th meter at the installation), register 1 applicable to a metering installation with the NMI of 2500012345.
• 2500012346 43 relates to accumulation energy data from a controlled circuit register in the 3rd meter at the installation, the data pertaining to a metering installation with the NMI of 2500012346.
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Appendix E: NMI allocation to metering installation types In the NT, the following situations provide insight into the allocation of NMIs for the types of metering installation to be deployed:
Power stations:
The largest annual flow of electricity is measured at the Channel Island power station. In 2015, the quantity was ~80,000 MWhs (80 GWh). This quantity was shared by three line metering installations, one of which was close to a balanced (zero) flow for the year. Accordingly, and assuming that the remaining two metering installations measured equal portions, the maximum flow for each metering installation would be ~40 GWh. This quantity equates to a type 3 metering installation.
Generators whose annual electricity volume per metering installation is less than 100 GWh but equal to or more than 0.75 GWh (750 MWh) are subject to type 3 metering installation accuracy. There is no requirement to provide a check metering (or partial check metering) arrangement for this volume range. Consequently, a single NMI will be allocated to this metering installation.
Zone substations:
The largest zone substation in the Darwin – Katherine power system has a capacity of 25 MW. At a load factor of 60% and two transformers, each with a metering installation, one of those metering installations would measure 66 GWh for a year, determined as follows:
Annual flow of electricity through one metering installation = 25/2*8,760*60%/1000 GWh
= 66 GWh
This quantity requires a type 3 metering installation per transformer. An annual volume of less than 100 GWh but equal to or more than 0.75 GWh requires only one master (revenue) metering installation. The metering installation would have a unique NMI.
As the annual volume per transformer is determined to be less than 100 GWh no requirement for a check metering arrangement is required.
Customers below 100 GWh:
For the full range of customers whose annual electricity volume is less than 100 GWh (down to zero MWh) there is no requirement to provide a check (or partial check) arrangement. Consequently, a single NMI will be allocated to this metering installation.
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Appendix F: Examples for the allocation of NMIs There are two categories of examples; one for interval metering installations (section F1) and one for accumulation metering installations (section F2).
The following legend is deployed throughout the examples:
F1 – examples for interval metering installations
F1.1 Contestable customer, metered on the lower voltage side of the transformer
Attributes:
• one connection point • one settlement point • one metering installation • one meter (single measurement element) • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream: 2500010101 E1
C
connection point
S
settlement point
transformer
meter
twin element meter, each element having its own register
Two register meter with single measurement element
Open switch
circuit breaker
M
MM
X
OO
metering installation (in part)
Closed switch
M
C
S
OO M
Page 19 of 33
F1.2 Contestable customer, multiple metered on the lower voltage side of the transformer
Attributes:
• one customer • one connection point • one settlement point • one metering installation • four meters (each with a single measurement element) • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
2500010101 E2 2500010101 E3 2500010101 E4
F1.3 Contestable customer, two tariff metering (general supply + off-peak) on the lower voltage side of the transformer
Attributes:
• one customer • one connection point • one settlement point • one metering installation • one meter (single element) – no load control device • one meter (single element) with a controlled load • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
2500010101 E2
C
S
OO
M
M
M
M
C
S
OO
M
M
Indicative only
Page 20 of 33
F1.4 Contestable customer, two controlled loads, one twin element meter
Attributes:
• one customer • one connection point • one settlement point • one metering installation • one meter (twin element) with a controlled load • one meter (single element) with a controlled load • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
2500010101 E2 2500010101 E3
F1.5 Contestable customer, two twin element meters
Attributes:
• one customer • one connection point • one settlement point • one metering installation • two meters (each with twin elements) • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
2500010101 E2 2500010101 E3 2500010101 E4
Indicative only
C
S
OO
M
M
M
Indicative only
C
S
OO
M
M
M
M
Page 21 of 33
F1.6 Contestable customer, multiple meters on low voltage side of multiple transformers in the same substation
Attributes:
• one customer • one connection point across three circuits • one settlement point across three circuits • one metering installation across three circuits • three meters (each with a single element) • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
2500010101 E2 2500010101 E3
F1.7 Three contestable customers, metered on low voltage side of multiple transformers in the same substation building
Attributes:
• three customers • three connection points • three settlement points • three metering installations • one meter (single element) per connection • three NMIs • allocated NMIs: 2500010101
2500010102 2500010103
• identity of collected meter data streams: 2500010101 E1 2500010102 E1 2500010103 E1
C
S
OO M
OO M
OO M
C
S
OO M
OO M
OO M
C
C
S
S
Page 22 of 33
F1.8 Two contestable customers, two separate HV supplies to two separate substations, both metered on LV side
Attributes:
• two customers • two connection points • two settlement points • two metering installations • one meter (single element) per connection • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
F1.9 One contestable customer, two separate substations adjacent to each other or one single substation with two separate transformers, with a normally open point separating the high voltage supplies into two sources
Attributes:
• one customer • two connection points • two settlement points • two metering installations • one meter (single element) per connection • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
C
S
OO M
OO MC
S
C
S
OO M
OO MC
S
open
Page 23 of 33
F1.10 One contestable customer, two separate substations adjacent to each other or one single substation with two separate transformers, with the HV supply originating from a single source and LV switchboard in common switch room. This arrangement also applies to two separate substations not adjacent to each other but on the same premise (eg: Darwin Casino LV supply)
Attributes:
• one customer • two connection points • two settlement points • two metering installations • one meter (single element) per connection • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
C
S
OO M
OO MC
S
Page 24 of 33
F1.11 Multiple contestable customers, high rise buildings
Attributes:
• five customers • one connection point • multiple settlement points • five metering installations • one meter (single element) per installation • five NMIs • allocated NMIs: 2500010101
2500010102 2500010103 2500010104 2500010105
• identity of collected meter data streams: 2500010101 E1 2500010102 E1 2500010103 E1 2500010104 E1 2500010105 E1
S
M
OO MC
S
S
M
S
M
S
M
Page 25 of 33
F1.12 Multiple contestable customers, high rise buildings
Attributes:
• three customers • one connection point • three settlement points • three metering installations • one and two meters (single element) per installation • three NMIs • allocated NMIs: 2500010101
2500010102 2500010103
• identity of collected meter data streams: 2500010101 E1 2500010102 E2 2500010103 E1 2500010104 E2 2500010105 E1
S
M
OO MC
S
S
M
S
M
S
MCustomer 1
Customer 2
Customer 3
Page 26 of 33
F1.13 One contestable customer with multiple supplies (eg: NT Casino HV and LV supply)
Attributes:
• one customer • two connection points • two settlement points • two metering installations • one meter (single element) per installation • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
F1.14 One contestable customer with standby supply (eg: Robertson Barracks, Darwin Airport HV supply)
Attributes:
• one customer • two connection points • two settlement points • two metering installations • one meter (single element) per installation • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
Note: the standby supply may be a second or more permanently closed supply, implying that each supply will have its own NMI.
• one Market Participant or customer • one connection point • four settlement points • five metering installations (including one check metering installation) • one meter (single element) per installation • five NMIs • allocated NMIs: 2500010101
2500010102 2500010103 2500010104 2500010105
• identity of collected meter data streams: 2500010101 E1 2500010102 E1 2500010103 E1 2500010104 E1 2500010105 F1
• one Market Participant or customer • one connection point • one settlement point (logical) • one metering installation • one physical meter (single element) at distant location • one logical meter (at wholesale boundary) • two NMIs • allocated NMIs: 2500010101
2500010102
• identity of collected meter data streams: 2500010101 E1 2500010102 E1
The logical meter corrects the physical meter for line losses.
OOM
S
X
C
Logical metering installation
M
Physical metering installation(distant location)
OO
Wholesale market boundary
wholesale market grid
Page 29 of 33
F1.17 Generating unit supply point at wholesale market boundary
Attributes:
• one Market Participant • one connection point • one settlement point (logical) • two metering installation s(type 1) • two meters (single element), one for revenue and one for check • two NMIs • allocated NMIs: 2500010101 • identity of collected meter data streams: 2500010101 B1 (master)
2500010101 C1 (check)
OO
M
S
C
master
Generating unit
M
check
Page 30 of 33
F1.18 Street lighting (type 7 metering installation)
Attributes:
• one customer • one connection point • one settlement point (logical) • one metering installation (type 7) • no meters (algorithm used in place of meters) • one NMI • allocated NMI: 2500010101 • identity of collected meter data streams: 2500010101 E1
OO
S
C
Logical metering installation
Wholesale market boundary
Lamp 1
Lamp 2
Lamp 3
Lamp 4
Lamp 5
Page 31 of 33
F2 – examples for accumulation metering installations (type 6)
F2.1 One customer, single meter with single register
Attributes:
• one connection point • one settlement point • one metering installation • one meter (single measurement element) • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream: 2500010101 11
F2.2 One customer, two meters with single register
Attributes:
• one connection point • one settlement point • one metering installation • one meter (single measurement element) • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream: 2500010101 11
2500010101 12
C
S
OO M
C
S
OO
M
Mbi-directional
Page 32 of 33
F2.3 One customer, two meters with one assigned to a controlled load
Attributes:
• one connection point • one settlement point • one metering installation • one meter (single measurement element) – no controlled load • one meter (single measurement element) – with controlled load • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream: 250001010111
2500010101 42
F2.4 One customer, two register meter with single measurement element
Attributes:
• one connection point • one settlement point • one metering installation • one meter (single measurement element) – with two registers • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream: 2500010101 11
2500010101 21
Indicative only
C
S
OO
M
M
C
S
OO M
Page 33 of 33
F2.5 One customer, two multi-function meters
Attributes:
• one connection point • one settlement point • one metering installation • two meters (each with two measurement elements and associated registers) • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream (meter 1): 2500010101 11
2500010101 41
F2.6 One customer, two multi-function meters
Attributes:
• one connection point • one settlement point • one metering installation • two meters (each with two measurement elements and associated registers) • one NMI • allocated NMI: 2500010101 • identity of collected meter data stream (meter 1): 2500010101 11
2500010101 41
• identity of collected meter data stream (meter 2): 2500010101 12 2500010101 42
